基于介观结构的饱和与非饱和多孔介质有效应力

发布时间：2018-03-01 10:10

本文关键词： 饱和与非饱和多孔连续体含液离散颗粒集合体介观结构的Voronoi胞元模型有效应力 Biot系数 Bishop参数　出处：《力学学报》2016年01期 　论文类型：期刊论文

【摘要】：基于描述含液颗粒材料介观结构的Voronoi胞元模型和离散颗粒集合体与多孔连续体间的介-宏观均匀化过程,定义饱和与非饱和多孔介质有效应力.导出了计及孔隙液压引起之颗粒体积变形的饱和多孔介质广义有效应力.用以定义广义有效应力的Biot系数不仅依赖于颗粒材料的多孔连续体固体骨架及单个固体颗粒的体积模量(材料参数),同时与固体骨架当前平均广义有效应力及单个固体颗粒的体积应变(状态量)有关.提出了描述非饱和多孔介质中非混和固体颗粒、孔隙液体和气体等三相相互作用的具介观结构的Voronoi胞元模型.具体考虑在低饱和度下双联(binary bond)模式的摆动(pendular)液桥系统介观结构.导出了基于介观水力-力学模型的非饱和多孔介质的各向异性有效应力张量与有效压力张量.考虑非饱和多孔介质Voronoi胞元模型介观结构的各向同性情况,得到了与非饱和多孔连续体理论中唯象地假定的标量有效压力相同的有效压力形式.但本文定义的与确定非饱和多孔介质有效应力和有效压力相关联的Bishop参数由基于三相介观水力-力学模型,作为饱和度、孔隙度和介观结构参数的函数导出,而非唯象假定.
[Abstract]:Based on the Voronoi cell model which describes the mesoscopic structure of liquid granular materials and the meso-macroscopic homogenization process between discrete particle aggregates and porous continuum. The generalized effective stress of saturated porous media considering the volume deformation of particles caused by pore hydraulic pressure is derived. The Biot coefficient used to define generalized effective stress is not only dependent on particles. The porous continuum solid skeleton and the bulk modulus of a single solid particle are related to the current average generalized effective stress of the solid skeleton and the volume strain (state) of a single solid particle. Describing non-mixed solid particles in unsaturated porous media, Voronoi cell model with mesoscopic structure for three-phase interaction of pore liquid and gas. Mesoscopic structure of liquid bridge system with double binary bond model under low saturation is considered. A mesoscopic model based on mesoscopic hydraulic mechanics model is derived. The anisotropic effective stress Zhang Liang and effective pressure Zhang Liang of unsaturated porous media are studied in this paper. The isotropy of mesoscopic structure of Voronoi cell model in unsaturated porous media is considered. The effective pressure form is the same as the scalar effective pressure assumed phenomenologically in unsaturated porous continuum theory. But the Bishop parameters defined in this paper are related to the determination of effective stress and effective pressure in unsaturated porous media. Based on the three-phase mesoscopic hydro-mechanical model, It is derived as a function of saturation, porosity and mesoscopic structure parameters, rather than a phenomenological assumption.
【作者单位】：大连理工大学工业装备结构分析国家重点实验室;
【基金】：国家自然科学基金(11372066) 国家重点基础研究发展计划(2010CB731502)资助项目
【分类号】：O357.3

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